Yams, big and small, grown in almost all parts of our beautiful island are a staple in every household. A culinary favourite, yams are popular and well sought after for its starchy richness and numerous health benefits. From the nearly 60 yam and tuber varieties grown in the island, Raja Ala or Purple Yams, are undoubtably one of the most delicious with a variety of gastronomic delights to tingle your taste buds.
Raja Ala (or Rajala), naturally grown in tropical countries, is a type of yam from the family Dioscoreaceae and genus Dioscorea, which consists of more than 600 species around the world. A vine that can grow from 15 m to 30 m, the origins of the Raja Ala is attributed to the South East Asian region, especially to the Philippines where it is a staple food source. In Sri Lanka, Raja Ala is considered to be a native species. The outer skin of the Raja Ala is bark-like and brown while the flesh inside takes on a purple hue (bright to dark purple)—hence probably the name Purple Yam, as it is commonly known in the English language.
Though not a common sight at dinner tables in urban Sri Lanka, Raja Ala is a popular source of food in the more rural settings where it can be easily found at Sunday fairs and even homegardens and backyards. Generally grown in the wet zone of the country, Raja Ala is also grown in dry zone areas such as Monaragala, Marawa, Thengallanda and Jaffna as well. A highly adaptable crop requiring low levels of agricultural inputs to thrive, when compared to vegetables or cereals, the Department of Agriculture highly recommends the cultivation of the species in all climatic zones of the Island.
Raja Ala is renowned for its unique properties that provide a myriad of health benefits and older and wiser generations of our country advise firmly to add some Purple Yam to complete a balanced diet. Full of vitamins, minerals and antioxidants, Raja Ala is especially rich in protein, vitamin C and beta carotene. Another important feature of Raja Ala is that it carries anthocyanins, which together with beta carotene is responsible for the purple colour of the yam. Anthocyanins are said to have many healing and preventative properties. Studies have shown that anthocyanins may have the ability to prevent or reduce the risk of diabetes, cancer, cell damage, microbial infections, obesity, cardiovascular diseases and inflammation.
Purple Yams, rich in anthocyanin, has shown to improve heart function and gut health while regulating one’s metabolism by increasing good bacteria in the stomach. It has restorative effects as well, aiding the reduction of fat in the liver and also helps to repair the cecum and colon after a high-fat diet. As such, adding purple yam to one’s diet can help to control body weight, increase good cholesterol levels, may help reduce asthma and overall present a better way to repair and keep one’s body healthy without resorting to medications. Purple Yam is also known as an immune booster and an anti-inflammatory. It is also a remedy for abdominal and intestinal cramping—grandmothers’ epicurean wisdom has included serving Raja Ala as a meal, especially at breakfast, when menstrual pains became too hard to bear. New mothers are encouraged to add Raja Ala to their diet as it is considered to be a food source that increases the production of breastmilk.
Due to the high levels of starch in Raja Ala, many recommend consuming it as a main dish. With its sweet and nutty flavour, in Sri Lanka, Purple Yam is mainly consumed boiled with coconut and some even recommend boiling it with milk to increase its nutritional benefits. However, one has to be careful when boiling Raja Ala in water as studies have shown this destroys the antioxidant properties of the yam. Therefore, it is recommended to boil the yam in a small amount of water when preparing.
With food and gastronomical journeys becoming more and more popular in Sri Lanka, the Purple Yam is now coming into culinary style with many dipping their hands to experiment and expand the culinary possibilities of the Raja Ala. Many are now sharing a variety of dishes including but not limited to curried dishes, side dishes, smoothies, puddings and congee to name a few. In other parts of the world, purple yams are turned into a powder or paste form and is used to colour baked goods and pastries. In South East Asian countries, the versatility of the Purple Yam is utilized fully where it is baked, roasted, boiled, cooked, fried, added to soups, and much more.
Undoubtably a culinary delight, be sure to include purple yam in your diet not only for its taste but for the multitude of health benefits that the yam can bring to your life.
Did you know?
In Sinhala Rajala is also known as Ratala and Kiri Kedol as well. In Tamil it is called Rasawalli or Rajawalli while in English it is named as Purple Yam and at times Ube.
One cup (100 grams) of cooked Purple Yam provides the following:
- Calories: 140
- Carbs: 27 grams
- Protein: 1 gram
- Fat: 0.1 grams
- Fiber: 4 grams
- Sodium: 0.83% of the Daily Value (DV)
- Potassium: 13.5% of the DV
- Calcium: 2% of the DV
- Iron: 4% of the DV
- Vitamin C: 40% of the DV
- Vitamin A: 4% of the DV
